5.30pm update

Karl Rove quits White House

President George Bush's chief political adviser, Karl Rove, is to leave the Bush administration at the end of the month, the White House said today.

Mr Rove, one of the most powerful White House confidants in recent history, is the latest senior official to leave a beleaguered administration.

In brief remarks at the White House, Mr Bush paid tribute to his long-time adviser.

"We've been friends for a long time and we're still going to be friends," Mr Bush said. "I would call Karl Rove a dear friend. I thank my friend."

Mr Rove replied: "Mr President, the world has turned many times since our journey began, it's been an exciting and eventful time. You have remained the same man. I will deeply miss my work here. I look forward to continuing our relationship."

The two men then hugged each other.

Mr Rove is leaving at a time when his political stock has sunk. Others who have quit the administration include Donald Rumsfeld and Paul Wolfowitz, both of whom played key roles in the Iraq war.

Mr Rove, 56, was among those questioned after the identity of the CIA agent Valerie Plame was leaked to the press.

He admitted telling journalists about Plame's identity, making five appearances before a grand jury but ultimately avoiding charges of perjury and obstruction of justice.

"I just think it's time," Mr Rove told the Wall Street Journal, which broke the story of his departure and described him as "Mr Bush's political alter ego".

Earlier this month, Mr Bush set up a possible court showdown with Democratic senators by citing executive privilege in rejecting a subpoena for Mr Rove to appear before the Senate judiciary committee in an investigation into fired federal prosecutors.

The president's opponents have sought to force Mr Rove and other aides to testify about the firing of nine US prosecutors last year, which Democrats said were politically motivated. Mr Bush and the attorney general, Alberto Gonzales, have said they were justified but mishandled.

In the interview with the Journal, Mr Rove revealed he had told Mr Bush of his desire to resign a year ago, but had stayed on because of events such as the Democrats taking control of Congress and pressing issues including Iraq and immigration.

Along with other top White House aides, he was told by the chief of staff, Josh Bolten, that he would be obliged to stay until January 20 2009 - the day the next president will be sworn in - if he continued to serve beyond a certain date.

"There's always something that can keep you here, and as much as I'd like to be here, I've got to do this for the sake of my family," Mr Rove said.

He made optimistic predictions on issues such as Iraq, saying the country would be "in a better place" as the US troop "surge" continued.

When the president's low, 30 percent approval rating was mentioned, Mr Rove insisted he would "move back up in the polls".

He said he believed Mr Bush wouldleave behind two lasting pillars of future foreign policy - that harbouring a terrorist makes a nation as guilty as the terrorist, and the act of pre-emption.

While he predicted a Democratic nomination for Hillary Clinton, he did so with a swipe, saying of the Democrats: "They are likely to nominate a tough, tenacious, fatally flawed candidate."

He also said the Republicans had "a very good chance" of winning the White House next year, adding: "If we keep our nerve and represent big things, we'll win."

Mr Rove has worked for Mr Bush since he campaigned to be a governor of Texas 14 years ago. Many attribute Mr Bush's presidential victory in 2000 to Mr Rove's strategy.

However, he downplayed suggestions of immense power, saying: "I'm a myth. There's the Mark of Rove. I read about some of the things I'm supposed to have done, and I have to try not to laugh."

Mr Rove will leave the Bush administration on August 31. It is not known who will replace him, but there is speculation that Mr Bolten will divide up his duties among more than one person.

The White House deputy press secretary, Dana Perino, said: "Obviously, it's a big loss to us. He's a great colleague, a good friend, and a brilliant mind.

"He will be greatly missed, but we know he wouldn't be going if he wasn't sure this was the right time to be giving more to his family, his wife, Darby, and their son. He will continue to be one of the president's greatest friends."

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